Contrary to common usage, gravity is not a force. It is a change in the dynamics of space, so in a gravitational field you are moving but feel like you are standing still. Actually you ARE "standing still" (relativistically speaking) while you are falling in a gravitational field; there is no force acting on you.
Propulsion is the work it takes to fight against the falling component of gravity, just like the pressure of the earth on your feet is doing the work of keeping you from falling toward the center of the earth.
The action-reaction component involves heating the air and the earth by pushing your propellant molecules earthward to maintain your altitude. Similarly, the earth heats up beneath your feet as the packed molecules of the earth fight against the natural tendency to collapse into the center.
Here is a question: If everybody in the Western Hemisphere jumped up and landed at the same time, would the earth shift twice? (Once for taking off and once for landing?) The answer is Yes, but while we were in the air, we would cause a shift in the other direction by attracting the earth toward us! The final effect would be zero, because the center of gravity (of us and the earth together) would not have changed.
Newton's third law states that every action has an equal and opposite reaction. In an airplane the action is the engine pushing the air behind it. The reaction is the plane moving forward. Also the airplane wings are angled so that air is pushed down making the air push the plane upward.
"Action and reaction", or "For every action there is a reaction"."Action and reaction", or "For every action there is a reaction"."Action and reaction", or "For every action there is a reaction"."Action and reaction", or "For every action there is a reaction".
A reaction force exists in an airplane due to Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. As the airplane's engines thrust air backward, the plane experiences a forward reaction force that propels it forward.
The Earth pulls down on you, but you pull up on the Earth!
The action is the Earth's gravity pulling down on the book. The reaction is the book exerting an equal and opposite force upwards on the Earth, though it is so small that it is essentially negligible.
Forces ALWAYS come in pairs - as in "action/reaction". The atmosphere is no exception. For example, if the air pushes an airplane up, then the airplane also pushes the air down.
Newton's third law states that every action has an equal and opposite reaction. In an airplane the action is the engine pushing the air behind it. The reaction is the plane moving forward. Also the airplane wings are angled so that air is pushed down making the air push the plane upward.
The reaction force in this scenario is the Earth's gravity pulling on the Sun. According to Newton's third law of motion, for every action force, there is an equal and opposite reaction force.
"Action and reaction", or "For every action there is a reaction"."Action and reaction", or "For every action there is a reaction"."Action and reaction", or "For every action there is a reaction"."Action and reaction", or "For every action there is a reaction".
A reaction force exists in an airplane due to Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. As the airplane's engines thrust air backward, the plane experiences a forward reaction force that propels it forward.
The Earth pulls down on you, but you pull up on the Earth!
They don't actually defy gravity. Rather, an airplane uses its wings to 'glide' amongst the air currents. It's a matter of Action=-Reaction. Because of the shape of the wings, most of the air will move under the wings, which causes the air density to heighten and the airplane will be pushed upwards. An airplane can rotate its wings, so it can choose whether or not it wants to go upwards or downwards. Apologies for my bad English, it's not my first language.
The action is the Earth's gravity pulling down on the book. The reaction is the book exerting an equal and opposite force upwards on the Earth, though it is so small that it is essentially negligible.
Very freely; Newton's law of action and reaction comes into full play.
Because it scientificallty proves that the force of gravity will knock you over
Airplane is a noun
The reaction force to gravity is the ground pushing back up against you with an equal force to support your weight. This is known as the normal force.